Current emission reduction pledges under the 2015 Paris Agreement are insufficient to keep global temperature “well below +2°C” in 2100 relative to pre-industrial levels and to reach targets of the United Nations Sustainable Development Goals. Even a full and timely implementation of the Paris Agreement will heavily impact the ocean. Increased political ambition is therefore required, as well as enhanced efforts of both mitigation and ecosystem and human adaptation. There is growing evidence highlighting the role the ocean plays in mitigating anthropogenic climate change (i.e., uptake and storage of heat and anthropogenic carbon), and the cascading consequences on its chemistry and physics (ocean warming, acidification, deoxygenation, and sea-level rise), ecosystems and ecosystem services.